1. Field of the Invention
The present invention generally relates to computer apparatus and more particularly relates to rack-mounted computer systems.
2. Description of Related Art
In the interest of installation floor space economy main portions of high capacity computer systems are often mounted in rack structures that typically comprise vertically elongated, floor mounted cabinet assemblies of standard sizes. The cabinet assembly conventionally used for this purpose typically includes a rectangular internal frame structure externally covered by removable panels. A front access door is pivotally mounted on the front side of cabinet assembly and is typically made of glass to expose various interior components of the overall rack-mounted computer system, such as monitors and various indicating lights, to view without the necessity of opening the access door.
One of the subsystems conventionally incorporated in a rack-mounted computer system of this type is a central server which is basically a high capacity computer operatively coupled to remotely located computer work stations. To provide access to the server components they are typically mounted in a server drawer structure slidably supported in the internal frame portion of the rack cabinet for movement relative thereto between a forwardly extended component access position, and a rearwardly retracted operating position.
As in the case of other types of computers, a server unit has certain operating components with a relatively low service access frequency requirement, and other operating components with a higher service access frequency requirement. For example, the power supply box in the typical server unit does not need to be accessed for service purposes nearly as often as the system planar board and associated riser cards in the overall server unit.
In relatively low capacity server units this variance in the service access frequency requirements among the various computer components within the server drawer is of little consequence since the components can be mounted within the server drawer in a generally side-by-side orientation in a manner such that essentially all of the components are exposed when the drawer is opened. However, in the case of high capacity server units many of the internal components become large enough in horizontal directions to require that they be vertically stacked within the drawer which, due to the standard horizontal width and depth of the rack cabinet within which the drawer is slidably mounted, has a maximum horizontal width and depth. This vertical stacking of the various server components within their associated slide-out rack cabinet drawer structure conventionally requires that each time a component within a lower section of the drawer needs to be serviced the computer components above it need to be laboriously removed to permit access to the lower components, and then re-installed after the servicing of the lower components is completed.
Another problem typically present in computer rack units of conventional construction has to do with the requirement of ventilating the rack cabinet interior for the purpose of dissipating operating heat generated therein by the various computer components. The traditional method of providing this needed cabinet ventilation is to continuously force a suitable quantity of cooling air from an external source thereof upwardly through the rack cabinet, from a lower end portion thereof, and discharge the cooling air from a top end portion of the cabinet.
However, since the server portions of many conventional rack-mounted computer systems are basically high capacity personal computers, their components are typically arranged (like their desktop counterparts) in a manner such that they may be most efficiently cooled using a horizontal flow of cooling air passed through the interior of the server unit. Thus, the traditional approach of forcing cooling air vertically through the rack cabinet may provide less than ideal cooling of the one or more server units in the overall rack-mounted computer system.
From the foregoing it can be seen that it would be desirable to provide improved rack-mounted computer apparatus in which the aforementioned component access and cooling problems are eliminated or at least substantially reduced. It is accordingly an object of the present invention to provide such improved computer apparatus.